Which is more selective, University of Illinois Urbana-Champaign or Boston University?

Boston University is generally more selective overall than the University of Illinois Urbana-Champaign. BU tends to have a lower overall admit rate, and it draws a very large national and international applicant pool for a relatively compact undergraduate enrollment. UIUC is also highly selective in several areas, but its overall admissions picture is broader because of its size and public flagship role.

One important difference is that UIUC’s selectivity varies a lot by major. Programs like computer science, engineering, and business at UIUC can be exceptionally hard to enter, in some cases tougher than BU for those specific fields. But across the university as a whole, BU is usually the harder admit.

The applicant pools are also structured differently. BU is a private university with one central admissions process and consistently heavy demand across its colleges, while UIUC admits into specific programs and serves a substantial in-state mission as Illinois’s public flagship. That public-university structure can make UIUC less selective overall even though certain colleges inside it are extremely competitive.

So for a simple overall comparison, treat BU as the more selective school. The main exception is if you are applying to one of UIUC’s most competitive majors, where UIUC can be at least as difficult, and sometimes more difficult, than BU.